| Mobile satellite communication system have widely used in national defense and civil fields, for it have high mobility. The changing of the moving carrier's azimuth, pitch, and roll angles makes the main beam of the antenna deviate from satellite and may possibly influence the communication quality or interrupt the communication. To built a stabilized system relative to the earth become the vital problem for keep communication well. So, it has both theoretical significance and practical engineering value on studying on antenna driving systems with high stability and good dynamic characteristics.The essence of the star tracing is that the central axis of the antenna's paraboloid of revolution point satellite all the time, and it can be simplified to the question that antenna's section normal pointing. It is known that 3 points of the space can determine a plane, so that choosing 3-RPS parallel mechanism to be antenna driving system was putting forward. The system has many advantages such as simple structure, good stability and quick responsibility, for it integrated stable platforms with rotating shaft and joints driving device. The research on this new antenna driving system was been launched, the main contents are presented as follow:1. For moving parallel mechanism antenna system, the building method of 3 coordinate on earth, carrier and antenna has been put forward. Coordinate systems transformation has been provided; the relation between the beam and the moving carrier has been built; the inverse solution of the mechanism has gained; the kinematic analysis has been performed; trajectory of work space and curve of rod length function has been given. For the catastrophe points of the rod length function, the solution has been given. The instantaneous character has been discussed from the velocity and acceleration analysis of the mechanism.2. Under unsteady situation, the kinematic simulation has been done in ADAMS, including varying yaw, pitch and roll. The result shows that the rod length function is continuous and differentiable, the antenna's beam is steady and the star tracing can be satisfied by this system.3. The control program was encoded by MATLAB and control has been performed by MATLAB united ADAMS. The post processing for simulation has been done. Analysis of trajectory and rod-length time function has been given. 4. The control program was encoded by MATLAB and control has been performed by MATLAB united ADAMS. Analysis of trajectory and rod-length time function has been given, and the maneuverability of the system has been proved.5. Developed the prototype, and did the experimental research including: coding control program with MINT language; controlled the parallel antenna to move in pitch angle, rotated with Z axes, searching satellite signals etc, and gained good results.
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